File:Penaeus diagram carapace.png|thumb|200px|Diagram of a prawn, with the carapace highlighted in red.
A '''carapace''' is a Dorsum (biology)|dorsal
(upper) section of the exoskeleton
or shell in a number of animal groups, including arthropod
s, such as crustacean
s and arachnid
s, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron